In the past two years, Republic Services and the Ratto Group of Companies have given a total of more than $20,000 to the campaigns of three sitting members of the Sonoma County Board of Supervisors — Shirlee Zane, David Rabbitt and Efren Carrillo — and one unsuccessful candidate, John Sawyer.

Quietly, some critics have complained the donations smack of political gamesmanship in the middle of a major decision that could benefit the two companies.

Zane, who accepted the most money from the two companies, led the advisory body of elected county and city leaders that helped craft the proposal to transfer solid waste operations to Republic and Ratto.

She received a total of $11,000 from the two companies, but dismissed the notion they have swayed her with their campaign contributions. She also noted that she has received far more in donations to her two campaigns for county office from Service Employees International Union Local 1021. Some of its leaders and members oppose the landfill deal.

"I have a diverse breadth and depth of donors," Zane said. "They don't own me. They don't own my decision-making."

Rabbitt has accepted $3,425 from the two companies since 2011 and Carrillo took $4,100, campaign finance records show. Supervisor Mike McGuire has declined contributions from Republic and records show no contributions from Ratto.

Campaign records for Supervisor Susan Gorin, who beat Sawyer last year, showed no donations from Ratto or Republic. Sawyer reported a $1,500 contribution from Republic.

Former county supervisor Eric Koenigshofer, now a spokesman for Ratto — and one of three former county boardmembers working for the pair of solid waste operators — called the campaign contributions a "normal part of being in the community."

"All of this is transparent," he said.

The other former supervisors involved in the issue are Ernie Carpenter, an advisor for Ratto, and Tim Smith, a consultant for Republic.